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Blog Post 9 – FSK441 and JT6M—High Speed Meteor Scatter Modes by K1JT
Wednesday August 5, 2009
This is Curt Black, WR5J, with the Educational Radio Net –
Please standby for a FSK441 Digital QST
Before the net: Please download tonight’s software – WSJT, Weak Signal Modes by K1JT and set it up according to the blog and WA-DIGITAL Yahoo Group instructions. You should already have it from Blog Post 8 – we are still using the WSJT software from Joe Taylor, just this week we will use two new modes – FSK441 and JT6M
The software at 5.5Mbytes is just a little too big to be downloaded to the Yahoo site, so, if you haven’t yet, folks need to go to the source:
http://physics.princeton.edu/pulsar/K1JT/wsjt.html
and grab the current WSJT version 7.03 – the download will include the users guide in English. Set up as follows:
1. Use the WSJT7 black and white DOS-like window to check your input and output device numbers –
2. then transfer that info to the colorful WSJT7 by K1JT window - look under the SETUP menu - OPTIONS choice and enter the AUDIO IN and AUDIO OUT device numbers you got from the first column on the DOS screen in step 1.
3. Also make sure you have set the MODE menu item to FSK441 and hit the MONITOR button.
4. Also left click on the TOL control (under the DECODE button and above the DEFAULTS button) to set the TOLERANCE to 400, the maximum. A Right Click would decrease the value.
5. Finally, start SPECJT by selecting it under the VIEW Menu. Arrange the windows so you can see each of them during the net
WSJT ("Weak Signal communicatons, by K1JT") is the DIGITAL FSK Meteor Scatter and EME Program and HF DX Program and Weak Signal Propagation Program written by Joe Taylor, K1JT. It is amazing – it allows digital communication using protocols explicitly optimized for a number of different propagation modes.
Last week we used JT65A which allows worldwide communication on HF or Moonbounce (EME_- Earth Moon Earth contacts with stations that (by moonbounce standards) are quite modest.
To determine EME Path Loss we need to know -
- Moon distance from either the transmitting or receiving station
- Transmitter station output in watts, expressed as ERP [roughly transmitter power output (minus feedline loss) x forward antenna gain]
- Receive station gain (actual receiver gain minus feedline loss, x antenna gain)
- The operating frequency of the transmitter and receiver
As the albedo of the moon is very low (maximally 12% but usually closer to 7%), and the path loss over the 770,000 kilometre return distance is extreme -- around 250 to 310 dB -- depending on VHF-UHF band used, modulation format and Doppler shift effects), high power (more than 100 watts) and high-gain antennas (more than 20 dB) must be used.
In practice, this limits the use of this technique to the spectrum at VHF and above.
The moon must be visible in order for EME communications to be possible.
Enough about Moonbounce – what about Meteor Scatter?
Meteor Scatter (MS) allows us to use frequencies that are higher than the “Maximum Usable Frequency” or MUF that is controlled by solar radiation acting on the earth’s upper atmosphere. Instead, we reflect signals in the 2 meter and 70cm signals (144 Mhz to 450 MHz range) back to earth with the trails of ionized gas produced by passing meteors.
WSJT/FSK441 is now the primary meteor scatter program and mode over nearly all the world. It is a High Speed MS mode. People have used SSB and Slow CW for meteor scatter work for decades – but it takes a sizable chunk of material to create sufficient ionization to get enough time to say much on either of those modes.
However, High Speed Meteor Scatter, HSMS, lets us use much smaller slices of time from the much more common and nearly constant stream of dust and sand being swept up by the earth.
There are a couple of flavors of HSMS. If I were writing this ten years ago, I would be pointing you to WinMSDSP a program to allow you to send CW at very high speed –when a ping was recorded, the software would slow that ping down and you would decode the CW by ear at whatever speed your skill allowed. HSCW has been largely supplanted by FSK441 with its amazing decode capability thanks to Joe Taylor’s digital skill. Just in case you want to try it, WinMSDSP is available here: http://www.qsl.net/w8wn/hscw/winmsdsp/setup.exe
HSMS is much more efficient than slow CW or SSB meteor scatter! Also, HSMS is usable every day of the year, not just during the peaks of major showers. This is because HSMS needs only the fractional-second underdense pings of sporadic meteors. These are available just about all the time. It is the best way to get your 144MHz signal out to between 500 and 1200 miles. Grids can be worked that aren't available by most other propagation types.
While we are practicing on 2 meters FM, the typical setup would be a 2 meter sideband rig in USB feeding a horizontally polarized directional antenna pointing toward some group of potential QSO partners or grid square on your need list. All the things that help with weak signal work like good feedlines and some power help but mostly it depends on the ionization of meteors providing a reflector to send your signal back to earth over the horizon. Luckily, even tiny grains of dust and sand are enough to give you a 1/10th second ping – and with HSCW or FSK441 you can get both call signs or your report into that tiny window.
Specifically:
FSK441 is a high speed meteor scatter mode at 441 baud or about 9000 letters per minute (1800 wpm). FSK441 uses 4-tone Frequency Shift Keying, It contains a number of features to increase its sensitivity and reliability over any other method now available.
Every so often, you will see reference to JT44 – that is the old name for JT65. The original JT65 is compatible with JT65A, Joe developed JT65B to have greater tolerance of frequency instability and suggested people move to JT65B, but the most used mode still seems to be JT65A. Check the Sked Pages such as http://www.obriensweb.com/sked/ and click the Digitalradio button.
We are exactly one week out from this year’s Perseid Meteor Shower. Check out
http://science.nasa.gov/headlines/y2009/31jul_perseids2009.htm
http://www.skyandtelescope.com/observing/highlights/36787804.html
Recall that your front windshield gets more bugs on it than the back window. For that same reason, on Tuesday night August 11, you might want to set your alarm for the predawn hours of August 12 when our part of the planet will be on the leading edge of plowing through the debris from comet Swift-Tuttle. From SpaceWeather: This year's Perseid meteor shower could be even better than usual. "A filament of comet dust that boiled off in 1862 has drifted across Earth's path and when Earth passes through it, sometime between 0800 and 0900 UT (1 - 2 am PDT) on August 12th, the Perseid meteor rate could surge to twice its normal value," says Bill Cooke of NASA's Meteoroid Environment Office.
That grain of sand or piece of dust, as it starts interacting with the atmosphere about 60 miles above the planet, is moving pretty fast – the Dutch Meteor Society has measured thousands of them and the fast ones are around 70 km per second, or about 160,000 miles per hour (recall that 60,000mph of that is just our velocity around the sun)
Remember, you don’t need a meteor shower to use the HSMS mode FSK441, but it doesn’t hurt to have lots of activity – and it serves as a reminder to use those rocks to get those grids.
If you want to set up a SKED go to
http://www.pingjockey.net/cgi-bin/pingtalk
HSMS Resources:
Book: "Beyond Line of Sight", edited by Emil Pocock. http://www.qsl.net/w8wn/hscw/papers.html
http://www.qsl.net/w8wn/hscw/hscw.html
http://www.nitehawk.com/rasmit/welcome2-1.html
METEOR SCATTER PROCEDURES FOR ITU REGION 2
(N & S America)
From: http://www.qsl.net/w8wn/hscw/hscw.html
This document describes the Standard Operating Procedures for HSMS (HSCW and FSK441) operation throughout the IARU Region 2, North and
In following these procedures, all stations using HSMS for meteor scatter communications within the
Note - Meteor scatter procedures for Region 1 are not the same, and EME procedures (worldwide) differ from MS procedures, and also differ on the various bands. See the appropriate documents for more, and use the proper procedures for the region, mode, and band. As the old saying goes, "When in
TRANSATLANTIC TESTS - As these tests become more common, it should be publicly announced what set of procedures are being used.
FREQUENCY DETERMINATION, FSK441 DIGITAL METEOR SCATTER:
The stated frequency is the USB dial reading.
FREQUENCY DETERMINATION, HIGH SPEED CW METEOR SCATTER:
The stated frequency is the signal's actual zero-beat frequency, or the frequency that would be displayed by a frequency counter during key-down.
Thus, when using audio-tone injection, the dial frequency is the desired zero-beat frequency minus the tone frequency.
For example: for a schedule on 144.110 - Transmitter VFO is set on 144.108 USB, 2000 Hz audio tone injected. Sked is thus made for "144.110" (or "144.110 ZB"). Receiving station will want approximately a 1500 Hz tone, so will put the receiver on 144.108.5 USB.
(This is using audio-injection J2A keying. Direct A1A make-break keying cannot be used in
METEOR SCATTER SEQUENCING:
On meteor scatter schedules using FSK441, the Western-most station transmits the first calling period. Since 30-second periods are used, this would be the first 30 seconds of each minute.
For HSCW schedules, the Western-most station transmits the first calling period (first minute) of each hour and half hour.
NOTE - This is for
("Western station transmits first" has been the procedure for
DXpeditions normally run all schedules and CQs using the same sequence, usually the first period, regardless of direction (recommended).
Also, CQs by any station may be on either period, and commonly are on the first period (because on MS a reply may come from any direction).
REQUIREMENTS FOR A QSO:
The same as for any mode of operation or propagation - an exchange of both call signs, an exchange of some type of information or report, and an exchange of confirmation of reception of the report or information.
When a station copies both calls, he sends calls and report.
If he gets both calls and a report, he sends his report & Roger.
If he gets report and Roger, he sends
When both get a pair of
IDENTIFYING: When the schedule progresses to the "Roger, Report" and later sections, calls are no longer being sent. To remain legal, the simplest method is this:
ON FSK441, activate the automatic ID in WSJT so that it will send your ID.WAV file at the proper time.
On HSCW, every ten minutes jump back to the first (calls-only) transmit buffer for about one second, then immediately return to the current transmit buffer.
REPORTS, EXCHANGE OF INFORMATION:
Except when something special is required for a contest, an exchange of any additional information is valid for a QSO. The commonly-accepted (and expected) exchange for all HSMS operation is the burst duration-signal strength report ("2-number" report). This is now standard worldwide for HSMS operation.
| FIRST NUMBER ( | --SECOND NUMBER (SIGNAL STRENGTH) |
| 1 - Ping with no info. (Not sent) | |
| 2 - ping, up to 5 sec in length | 6 - up to S3 in strength |
| 3 - 5-15 sec in length | 7 - S4 to S5 |
| 4 - 15-60 sec burst | 8 - S6 to S7 |
| 5 - over 60 sec burst | 9 - S8 and stronger |
(In Australia where all MS operation is FSK441, there is a slight modification of this, with "06" meaning "20 ms, 0 to 10 dB," "17" meaning "40 to 80 ms, 11 to 16 dB," etc. See their HSMS Web sites for more).
Note that there cannot be any confusion between the first and second number as the ranges do not overlap; also note that the second number is not itself an "S-meter reading". (The duration report suggested here is slightly different from the European standard and also from some of the older North American charts).
This is now the preferred exchange for HSMS operation. But, if the other station uses a different reporting system, simply copy what he sends and send your report.
The typical ping will have a Burst Duration of 2, a Strength of 6. (This is a weak-signal mode).
Once you have started sending a report, it is NOT changed during that schedule, even though you suddenly get a much better burst. E.g., if you start sending "26", this is the report you would continue to send, even if you next get a "38-quality" ping. Changing the report could result in the loss of a contact.
Note on WSJT's FSK441 North American reporting: The #2 Standard Text Box defaults to "Firstcall report Secondcall report report" (e.g., K1JT 26 W8WN 2626). The reason for this format is to allow monitoring stations to tell which station they're hearing. Since the pair of calls is the longest string of text to exchange, lower-power stations may find it advantageous to change this to "Firstcall report Secondcall report" or even "Firstcall Secondcall report."
This change is definitely recommended for contests when the
Other sometimes-used exchanges:
Burst length "S" report. Standard in
Grid square. Required for most contests. Sometimes used by portable or /MM stations; however, on FSK441, it is becoming common for the portable or /MM station to include their current grid in the CQ . The grid square normally should not be used on HSMS for the report except for contests.
An exchange of Rogers (R's) is necessary to complete a contact, regardless of the mode. But how many R's are required? It's much like the old question, "How many angels can dance on the head of a pin?"
Regardless of mode, only one (1) Roger is actually required. But are you sure you received it? Was it really an R? Many EME and MS operators have been greatly saddened to learn that the "definite R" they received was actually another letter, chopped up! This is why most operators don't trust conditions and their hearing to accept a single, isolated R, but prefer to have 2 or more.
So how many R's are required? As few or as many as you need to feel comfortable that you have it! If you rely on only a single R, many times you'll be correct. But all too often you'll later learn that the other station was not sending R's and the contact was not completed. (Those of us who have been on MS and EME for awhile have experienced this all too often - from both ends!)
MISSING INFORMATION:
On High-Speed CW MS operation, it is possible to request a missing piece of information.
Note - this does not work as well for FSK441, but could possibly be used. (On FSK441, it's best to just ask for the needed information as these letters are likely to be interpreted as only gibberish).
BBB - Both call signs needed
MMM - My call sign needed
YYY - Your call sign needed
SSS - Report (or whatever report/information exchange used) needed (some have suggested GGG for needing the grid)
UUU - Ur keying is unreadable
(Use "U" when needed. Remember that the other station cannot monitor his keying).
These "requests for repeat" letters are used only when the other station mis-copies something and jumps ahead in the sequence. Thus, they are seldom needed (but very valuable at that time).
When these are used, nothing but the appropriate string of letters is sent. (E.g., "YYYYYYYYYY").
The other operator should respond by sending only the requested information. (E.g., "W8WN W8WN W8WN").
When the requesting operator has the needed data, he returns again to the proper exchange sequence.
HSCW SPEEDS:
For CQs, a speed of 6000 lpm has now become standard in
HSCW SCHEDULES - always determine what speed the other operator wishes to use. If you are very far off the other station's speed, not only is copy impossible, you can't even tell whether he's a lot faster or slower than your settings!
The most effective schedule speeds with current equipment and techniques are 6000-10,000 lpm. The signal-to-noise ratio becomes poorer above about 12,000 lpm; thus, higher speeds are not recommended for routine operating, although a number of stations are testing various techniques for use at these higher speeds.
FREQUENCY USE:
SCHEDULES:
Schedule frequencies are arranged between the two individual stations on any seemingly unused frequency.
On 144 MHz, North American HSMS operation is normally conducted between 144.100 and 144.200 to avoid interference with EME operation below 144.100, and with SSB operation near and above 144.200.
(Remember, in the
At this time, most 50 MHz schedules are being made between 50.240 and 50.310.
Schedules should always be made at least 5 kHz away from the calling (CQ) frequencies.
(Speeds, frequency, exact procedures, etc., must always be confirmed between the two stations, especially if something different from the standard procedure is desired or one of the operators is new to this mode).
CALLING CQs - no offset:
On 2 meters - 144.140 dial for FSK441 and 144.100 zero-beat for HSCW. Call, listen, and operate on the same frequency, unless there seem to be several stations operating there. If this is the case, the CQ-Letter or Uxx/Dxx method should be used.
On 50 MHz - 50.260 dial for FSK441 and 50.300 zero-beat for HSCW.
Either period may be used, since they could be answered from any direction (see sequencing).
HSMS CQs on other frequencies are almost certain to be unsuccessful unless they have been announced on the proper real-time Web site.
Note - except during contests or other periods of high activity, it is always necessary to announce that you are going to call a CQ.
For other VHF/UHF bands, no calling frequencies have been decided on. Due to the difficulty of operating MS on 220 and 432, all operation is currently by means of schedules.
CQ, OFFSET LISTENING:
FSK441 - If it is apparent that there are several operating, immediately following the letters "CQ", a specific letter and number are inserted to indicate the frequency that will be used for reception when the CQ sequence ends.
For example: "CQU5" means "I'm listening and will reply Up 5 kHz."
"CQD8" means "I'm listening and will reply Down 8 kHz".
The offset frequency is always relative to the CQ frequency. Thus, "CQU8" on 144.250 would mean that the contact will take place on 144.258 MHz. (144.250 is not a good frequency for an HSMS CQ, but is simply used as an example).
When using FSK441, instead of sending Up or Down, you could specify the actual frequency, such as "CQ 123" would mean "I am listening and will answer on 144.123 MHz."
When the CQing station hears a call on the offset frequency (not on the CQ frequency, for he is not listening there), he/she immediately then also moves to the offset frequency, and the QSO takes place there with BOTH stations now transmitting and receiving on the new designated frequency.
HSCW - If it is apparent that there are several operating, immediately following the letters "CQ", a specific letter is inserted to indicate the frequency that will be used for reception when the CQ sequence ends. This letter indicates the frequency offset from the actual CQ calling frequency used. For example, "CQE" would indicate that the CQing station would listen 5 kHz above his CQ frequency. In all cases the letter used indicates a frequency higher than the CQ frequency. When the CQing station hears a call on the offset frequency (not on the CQ frequency, for he is not listening there), he/she immediately then also moves to the offset frequency, and the QSO takes place there with BOTH stations now transmitting and receiving on the new designated frequency.
For example:
CQC - Up 3 kHz
CQE - Up 5 kHz
CQZ - Up 26 kHz
CQAA - Up 27 kHz. Etc.
Note that the letter indicates the number of kHz higher than the CQ frequency. It does not indicate any specific frequency. Thus, if a DXpedition is using some other frequency for CQs, the letter again indicates the number of kHz higher where they are listening and to which they will QSY for QSO attempts.
CQ with
ANSWERING A CQ:
If it is only a straight CQ, you transmit and receive on the frequency that is being used for the CQ.
If it is a CQ-letter or a CQUxx or CQDxx, you change both your transmitter and receiver to the indicated frequency.
You then call and listen on this new frequency. When (if) the CQing station copies both calls, he will also QSY to this new frequency and the contact will take place there.
WARNING - Even during a major shower, pings may be few and far between. When you reply to a CQ, do not quit after only a few minutes. It may require 20 minutes, 30 minutes, or longer before the CQing station copies your call and you get a ping back from him. Plan to continue calling for a while.
When you call the CQing station, you use the standard 1x1 calls (e.g., W4HHK N1BUG W4HHK N1BUG, etc. - NO reports. [This is different in
When the CQing station copies you (on the new frequency, if a CQ-letter or CQUx or CQDx has been used), he will respond with both calls and a report.
The calling station continues with the 1x1 calls until he copies the calls and report, then switches to the Roger-Report, and then on through the usual sequence.
(If the CQing station gets only partial calls, he should QSY and call "QRZ?" on the new frequency).
OTHER:
Schedules are always made in Universal Time. However, for evening schedules, the local time/day may also need to be stated to be certain that the date is understood properly.
USE OF THE WEB, HF, ETC, DURING A CONTACT:
The Internet has made the setting up of schedules, checking results, real-time help, etc, very easy. Its use (and other, similar methods) are always encouraged for these purposes.
But what about confirming individual portions of a contact in real time, while the contact is in progress? (E.g., "OK, I have your calls and report, I'm sending R26s now", etc).
This depends upon the purpose of the attempted contact. For many contests, this is not allowed. And if contact by any other means is made while the attempted VHF contact is in progress and any information concerning the contact is exchanged, the contact must be restarted again from the beginning.
For claiming a record, or for a new state, etc, while not technically "illegal", it is strongly frowned on and discouraged. Most VHF operators do not communicate with the other station by the Internet (or similar means) from the time the contact has started until it has obviously been completed (i.e., one station has received "73").
Obvious exceptions to this would be if there's a major problem at either end (need to change frequency, rig problems, the other signal is not readable, etc), or incidental comments having nothing to do with the contact in progress.
For routine contacts, tests, experiments, etc. with a station you've worked many times, obviously there's nothing wrong with comments concerning the contact, for you won't even bother exchanging QSLs again. And the Internet is a great way to help fellows set up their rig, learn the proper procedures, and get things operating properly.
The bottom line is, what is the purpose of the VHF contact? If it's really to make this VHF Contact, it should be made on VHF with no outside help, once the schedule is set up and started. If it's completely routine, one contact of many with that station, for tests or help, etc, and it really doesn't matter whether or not the contact is completed, then it really doesn't matter what else you're doing at the same time.
These are the current HSMS Procedures for Region 2. If you wish to experiment with variations, that is up to you and the other station; this is the way the procedures grow and improve. But by using these for routine operating, you are less likely to disappoint the other station by seemingly failing to show up for the schedule, or by not knowing what to do!
SSB METEOR SCATTER PROCEDURES FOR REGION 2:
SSB exchange requirements and procedures are the same as HSMS procedures, with the following changes:
- The period is normally 15 seconds, with the Western station again calling first at the start of each minute.
- Random MS operation does not necessarily follow an exact sequence. Break-in is commonly used.
- Information exchange (report) is usually the burst-length "S" report (S1 through S5) on schedules, Grid Squares on random contacts. For random contacts, yet other exchanges are sometimes heard.
- Phonetics must be used for random operation; they should not be used for schedules.
- For CQs, the usual SSB calling frequencies are usually used during periods of low activity. However, during the peaks of major showers, they quickly become overcrowded. Frequencies every 5 kHz above and below the calling frequencies are then commonly used.
- On SSB, attempts are usually made to complete the entire QSO on a single long burst. Thus, break-in procedures should be used whenever possible.
"SLOW" CW (UNDER 50 WPM) MS PROCEDURES FOR REGION 2:
Again, the procedures for CW are the same as for HSCW or SSB, with the following changes:
- The period may be 15, 30, or 60 seconds. Thus, this must be stated.
- The exchange (report) is normally the burst-length "S" report.
- Random CQs may follow the 15-second sequence, or they may be short calls with a break.
JT44/JT65 OPERATION:
JT44 and JT65, other weak-signal modes of WSJT, are useful for distances too short for meteor scatter operation but where tropo scatter might be possible, and especially for EME operation. They should also be good for TE, IOS, and other modes of propagation where the signal is expected to be very weak but more or less steady.
For terrestrial JT44/JT65 operation (i.e., not EME), procedures, sequencing, etc., may be either the same as for MS or for EME! Therefore, the sequencing must be stated and agreed on prior to each schedule.
Frequencies used are in the same portion of the band as used for meteor scatter operation. There is no commonly-accepted frequency for CQs, though 144.163 has been proposed.
For JT44/JT65 EME operation, the procedures are generally the same as worldwide EME procedures for the band in question, except for the length of the transmit period (30 seconds for JT44, 60 seconds for JT65).
On 144 MHz, two sets of frequencies are currently in use - 144.105-144.135 and 144.145-144.170. EME JT44/JT65 CQs are most often simply announced on the JT44 EME Web page.
Japanese stations must operate above 144.4.
(Remember, in the
This "Procedures" paper is primarily for meteor scatter operation. JT44/JT65, both EME and terrestrial, are too new for all of the procedures to have been worked out. If you have questions, people on the "Ping Jockey" and "JT44" real-time web pages, as well as the "HSMS/JT44 Reflector," should be able to give you the latest information.
FOR MORE INFORMATION:
Region 1 Meteor Scatter procedures can be found at URL http://www.scit.wlv.ac.uk/vhfc/iaru.r1.vhfm.4e/5B.html. (Due to be revised soon).
This Region 2 document covers only the basic procedures. For more General HSCW information, go to http://nitehawk.com/rasmit/ws1_15.html or http://www.qsl.net/w8wn/hscw/hscw.html, and follow the links. Charts and many other papers are available to assist with both operating and technical information.
To download the latest version of WSJT, go to http://pulsar.princeton.edu/~joe/K1JT/, or the mirror site at www.vhfdx.de.
To keep up with what is happening on meteor scatter, JT44 operation, and general VHF news, check the Hot News Page regularly at http://www.qsl.net/w8wn/hscw/papers/hot_news.html.
WHAT IS THE BEST TIME FOR METEOR SCATTER OPERATION?
SPORADIC METEORS
In the morning hours, around 0600 local time, that part of the earth is facing the same direction as the direction of travel of the earth in its orbit around the sun. Thus, not only are meteors swept up which are heading toward the earth, but the movement of the earth around the sun allows it to catch up with some of the slower meteors and pull them in, also.
On the evening side (facing away from the direction of the earth's orbit), the only meteors reaching the earth are those which can overtake it.
The best time for visual observing is considered to be between 2 and 4 am local time. This is because during the season when the sporadics are at their peak (summer), the sky brightness is increasing after 4 am.
It must be remembered, however, that many or probably most "sporadic" meteors are actually the remains of long-gone showers. Thus, on a given day, there could be meteors from 5 or 6 of these "extinct" showers hitting the atmosphere, causing an enhancement at an unexpected time.
There is a considerable seasonal variation of sporadics, also, with February being the low month and July being the highest. (KB0VUK has a chart of this on his Web page). Note the number of major and minor showers in the June-September period and the reason for this will become obvious.
There are also several other factors that influence the number of sporadics, and also the ratio of morning to evening. But these are not that important. Just be aware that the variation can be significant month to month, day to day, and even minute to minute!
The best reference for MS operation is still the second article by W4LTU, reprinted in "Beyond Line of Sight" (available from the ARRL). This is NECESSARY reading for anyone thinking of MS operation. Also, see the text files that accompany OH5IY's MS-Soft program.
Yes, HSMS is possible any time. But there are 4 to 6 times the average number of sporadics at 6 a.m. local time than at 6 p.m. On a good path, evening HSMS operation is quite possible; and the pings, while fewer, often seem to be stronger in the evening. (On a difficult path, unless there's a shower peak, I wouldn't try evenings. There just are not enough sporadics).
SHOWERS
The peak of a shower may come at a time other than the 4-8 a.m. period, of course. In this case, the maximum rate may be at some other time of night (or day - remember that there are a number of daylight showers, too. These are seldom mentioned because visual observers can't experience them).
Some showers are spread over several days, others have VERY sharp peaks. As of now, these peaks can be predicted only very generally, and may be off by many hours. Their intensity may be off by an order of magnitude or more, also. This is because all predictions in the past have simply placed the probable peak time at the time when the earth's orbit should cross the orbit of the meteor stream. However, this does not take into account any variations, simply assuming that the meteors are now spread out evenly in their orbit. But, as has been realized in the past decade, this often is not true. Especially for streams that may have established a resonance with Jupiter, a stream may be bunched in filaments, as the Leonids have proved to be. Because of the work of Asher, McNaught, and others, predictions in coming years may begin to improve greatly in accuracy. For more on this subject, go to The Upcoming Leonids Storms, the Archived News Page and also the pages of Asher and McNaught, who are revolutionizing meteor shower predictions with their dust-trail model.
The big mistake most operators make during a shower is trying to operate using shower meteors when the shower radiant is below their horizon. The radiant is the point in the sky from which the meteors appear to come. If this part of the sky is still below the horizon, the number of shower meteors available for your use is going to be low. Yet during every major shower, stations will be heard on 144.200 calling long before the radiant rises.
If you're operating HSMS, you may be able to catch enough sporadic meteors almost any time of day or night, even during the early evening. However, for slow CW or SSB, when overdense bursts or a number of good underdense pings are needed, it is of little value to operate when shower meteors are not expected! See the tables in W4LTU's articles, or use OH5IY's MS-Soft program to determine the rise and set time of the radiants of the various showers. (You will also note that, until the radiant's elevation is up 30 degrees or so, it isn't considered a very good time for their utilization).
This page contains only the most basic information on sporadic and shower meteors. To be successful during showers, you must study W4LTU's articles and the text files bundled with MS-Soft, here: http://www.kolumbus.fi/oh5iy/ . Then watch the "Hot News" page for the latest predictions (remembering, however, that the peak times for the showers will continue to be only approximate). For HSMS operation, except for difficult paths, use the daily sporadic meteors, or the beginning and end days of a major shower. During the peak of a major shower, SSB is probably going to be more efficient. But plan your SSB schedules when the radiant is at a proper elevation if you expect results. Study the articles referenced above, read the other papers on this Web site and the W6/PAØZN Main NA HSCW Web Site, and follow the links from these papers and from the list of other Web sites that each HSMS Web site maintains.
Here is the etiquette section from http://www.qsl.net/wa5ufh/DOS/Etiquette.htm
Ping Jockey Etiquette
Men have a hard time remembering which fork to use, the long one or the short one. Which side of the plate does the napkin go? How many times is it appropriate to stir the tea after the sugar is added. The steak can be eaten with the short fork and the tea beat into submission, but it is not always considered proper etiquette.
We all know there is behavior on the Ping Jockey that is acceptable during a contact attempt and behavior that is just not as acceptable. This page will discuss Ping Jockey Etiquette and to my knowledge most of these things are not documented like the proper table etiquette thus our thoughts are conceived from what seems proper and valid.
Ping Jockey Schedules
Amateurs who operate High Speed Meteor Scatter are completing qso’s daily, or are they? Typically qso’s are either scheduled or random. Schedules are easily arranged via the Ping Jockey Page. Schedules that are made have an advantage over random qso’s because the two stations share important information via the internet prior to the start. This often times includes:
• The call of the other station
• A specified frequency
• Who will transmit first
• Will Single Tones or Multi-tones be used
• Which Azimuth direction will be used
• Often times QSY to another frequency because of perceived interference
• A start time or announcement of “ I am running” or both
• Sometimes a ending time is set in case the communications fail
• Equipment conditions / parameters
• Noise descriptions or lack of noise
(And often times much more!)
With all the discussions and exchange of information before the actual attempt to communicate, one might wonder; how could they fail? Of course we all know that meteor scatter contacts are not automatic. There are times when attempts just fail, for whatever the reason, even with all the prior knowledge shared before the attempt.
The known elements shared before attempts are good and the smart operator will use them to his advantage. However to reduce the clutter on an often times busy page the information exchanged prior to the QSO start should be short and precise.
What Frequency will we use?
Who will go first? (Savvy operators know based on the Standard Operating Procedures
When will we start / stop?
Do you want to use ST or all MT?
(This is off topic BUT schedules should not be made on Meteor Scatter Calling Frequencies)
What Constitutes A Contact
This has been decided years back. Both stations must copy "Both Radio Calls", and "both must also copy their respected report and at least one Roger" (you usually need at least two
Either stations, or at least "the station receiving the
The validity and integrity of the following list of accomplishments by stations can be “brought into question” when contact requirements are communicated, hinted or suggested by the use of the Ping Jockey either by those attempting to make a contact or someone monitoring and posting what they are copying.
• VUCC
• States Worked
• Initial Contacts
How far can we go before the Contact becomes invalid?
First let us consider this fact. WSJT works sufficiently well so that no other means of sending or sharing information is necessary to complete a contact via meteor scatter. Thus it is not necessary for meteor scatter operators to give out informtion about the contact during the contact. For schedules, everything is worked out ahead of time and after the contact starts it is not good etiquette to discuss, hint or share information pertaining to the contact attempt that is in progress! There will be some who think other wise, but the divisions are, make the schedule first and execute the schedule second.
The operators of WSJT, from the beginning of Ping Jockey asked that the following message to be posted for all new and experienced operators. That message is “Exchanging any contact details on here before you're complete, invalidates the contact”
The following are examples of statements that would certainly call into question a contact by either attempting station. Blatant communicating contact details during a contact attempt are wrong!
Have you gotten both calls yet?
Sorry I skipped a message, going back to Calls and Reports
Sending RRR now.
I just got your Report.
What message are you sending?
Have R 26, I am sendng RRR now.
From the beginning of HSCW, Operators have always considered contact details to be information about the details of what is or has been sent.
The following examples are statements that don’t exactly tell where you are in the contact but like setting the table wrong or eating the steak with the short fork, are better just not said.
• Are you sending single tones now?
• I can hear you now
• I have up to 10db burst no decodes
• Just got a big one!
• Keep going
• Your DF is 102
• Leave your antenna there!
• Not hearing anything, moving to Hot A
• I am getting some single tone, is that you?
• Wow! You hit me hard, 13db!
• Keep going we are almost finished.
• There is 500 watts out have anything yet?
Sometimes the contact is compromised by someone who is just monitoring.
I hear your single tones good here Joe!
They are almost finished Joe is sending reports now.
Look what I copied 155630 27.4 240 1 26 -64 2626 WA5UFH 26 K4FJW (be careful what you post)
There are many ways that a contact can be compromised. What should one do when this happens? The best answer is to start over! That is the right thing to do and easily done. If the qso was compromised by a contact station, the offending station should be reminded to read the “Blue” line at the top of the Ping Jockey Page. Meteor Scatter is a valid mode and all operators should honor the requirements for completing contacts strictly via Meteor Scatter refractions on our vhf bands.
Is there ever a time for compromising a contact by sharing contact information?
The answer is no!
Meteor Scatter Contacts never involve the sharing of QSO details after the contact is started. Not even a hint or suggestive statement is good etiquette. If contact information is shared, even though all elements might have been received by both stations, the contact was tainted and does not meet the requirements of using “Meteor Scatter Only” for the exchange. The trail of suggestive or shared information relating to the “supposed contact” is on the Ping Jockey screen for all to view. As stated earlier, WSJT is capable of transmitting all the required data via your radios and meteor scatter.
Is it acceptable to QSY to another Frequency because of QRM or QRN?
If QRM has creped into your passband and might cause you to miss some received messages then the smart thing to do is QSY to another frequency. This can be accomplished by posting the need to QSY on the Ping Jockey without sharing any contact details.
What if I have a catastrophic failure?
Anytime a contact attempt is terminated and is latter restarted, both stations are to start over at the beginning. If you must stop, the courteous thing to do is notify the other station you have stopped. A temporary problem can be posted like, keep going I am having a temporary problem and not compromise the contact. Often times a problem can be corrected easily without terminating the contact attempt.
What if it’s not a Contact?
Now if it’s not a contact, let’s say someone asks you to listen for their signal and see if they are on frequency or maybe they are testing their transmit for the fist time. Talk all you wish, this is not a contact. The majority of what occurs on the Ping Jockey constitutes a contact where two amateurs agree to have a prearranged sked for the purpose of completing a contact. If you have worked the same station 100 other times, the rules for a contact do not change just because you have his card on the wall.
Ping Jockey Etiquette; “Because I respect the Posted Guidelines on the page”
Ping Jockey is a useful system for Meteor Scatter operators, Weak Signal Operators and EME scheduling. The Ping Jockey pages are self explanatory however many seem to be happy carrying on all their business on the Ping Jockey Central. Ping Jockey Central, the main page, is not designed to be a “Chat Room”. At the top of the page we all see the message, “If it's not HIGH-SPEED METEOR SCATTER, it doesn't belong here! Even with this message, we find discussions about antennas, radios, club meetings and many other discussions not relating to HSMS!
There is another page called “Relief Page” that is similar to the Main Page but because of less activity it will support discussions and the appropriate thing for operators to do is move off topic discussions there just like it is appropriate to move stations willing to run JT44 off the Ping Jockey Central page to the JT44 Link page.
The other pages, CQ Announcements and Skeds in Progress are self explanatory and during times of higher volume traffic, like contests, these pages should be used to reduce the potential of qrm.
We are fortunate to have such a system as Ping Jockey. We should all thank Chris often and we should honor his posted instructions.
So What Can I Do During a Contact Attempt via Meteor Scatter
Computers are multitasking. One can play cards, surf the web, clean the shack, read email, work on the projects bench etc. but please, don’t bring any element of doubt on your contacts or your friends contacts by posting information about the contact prior to it being completed.
Why This Article?
I am not without guilt. I suppose we all have been guilty of some questionable act relating to meteor scatter. We should all strive for a higher operating plane and the experienced should lead by proper example. Before things get too far out of hand, let us all focus on Meteor Scatter Only Contacts.
Make the sked on Ping Jockey and then execute the sked on the radio.
Thanks to all those who helped critique this sheet. ( WB5APD,N0UK,K1SIX and others...)
WA5UFH (Tip)
Next week: Packet Radio and Airmail
That setup is a little more complicated than the others we have done to date. Since it has a few steps, I put the materials and software on the WA-DIGITAL site a few weeks ago. Check out Blog Post 10 for the setup. Of course, if you are using a hardware TNC for packet decoding, then just hook up your TNC and you are good to go…
Write with any questions - See you on the bands!
vy 73 de WR5J
Curt Black – black@nwfirst.com
1 comment:
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